Development of Remote Cooling Systems for Low-Temperature, Space-Borne Systems
T. Nast, J. Olson, E. Roth, B. Evtimov, D. Frank, P. Champagne
Lockheed Martin ATC, Palo Alto, CA
AbstractLockheed Martin's Advanced Technology Center (LMATC) has developed advanced cryocooler technology to provide temperatures of 10K and below for cooling space and terrestrial payloads. For some payloads, cooling is required remote from the cryocooler. Over the past few years we have developed numerous staged coolers, which provide temperatures as low as 3.8 K, and are extending this technology to provide remote cooling while maintaining our simple, high-reliability approach.
Our approach employs our multiple-stage pulse tube in combination with an integral flow loop. This flow loop circulates a small fraction of the working fluid from the cryocooler compressor. As a result, only a single compressor is required. The flow loop utilizes constant (DC) flow to provide cooling at temperatures near 6K at the remote cooling location. No Joule Thomson (J-T) expansion is utilized in this approach, greatly simplifying the hardware and reducing the number of components. This approach increases reliability and reduces weight compared with the J-T approach. Our four-stage pulse tube cryocooler was developed under the very successful Advanced Cryocooler Technology Development Program (ACTDP) under contract to the Jet Propulsion Laboratory (JPL).
The development of the remote cooling loop was jointly supported by JPL and LM research funding. Extensive performance data for the four-stage ACTDP pulse tube cooler are described. In addition, preliminary data and performance of the pulse tube system, integrated with a 20-meter long flow loop, are also presented.